Isolated thunderstorms are possible Wednesday afternoon but flooding concerns in Oklahoma should decrease throughout the week.

The heavy rains and flooding are the result of a strong low pressure system that covers the southern US and will continue to push a cold front eastward throughout Wednesday, according to Weather Underground. Flow around this low pressure system pulls warm and moist air in from the Gulf of Mexico and triggers more heavy rain and severe thunderstorms across the Lower Mississippi River Valley and Southeast. This system will continue causing major flooding problems as it moves eastward throughout the day. Rainfall totals are likely to surpass 3 inches in some areas. There is a a slight chance that severe thunderstorms will develop over the Southeast on Wednesday. If storms turn severe, expect strong winds, large hail, and possibly a few tornadoes. After the cold front passes, slight cooler temperatures are anticipated. Expect highs to range in the 60s and 70s across the Central US.

A flood warning remains in place in Oklahoma for the Poteau River near Panama in LeFlore County. The river was at 35.43 feet Wednesday morning — that's more than 2 feet above moderate flood level. Hydrologists predict that the river will crest at 37.2 feet Wednesday evening before dropping below flood stage on Thursday.

The weather service says crops and pasturelands could flood between Shady Point and Arkoma in eastern Oklahoma near the Arkansas border.

The National Weather Service issued flash flood warnings Wednesday for much of Arkansas — including the Little Rock metro area — as rainfall continues to inundate the state.

Forecasters say flash flooding is likely in central Arkansas, where several roads are closed because of high water. Authorities say they've received reports of flooding on Crystal Hill Road in North Little Rock and along Baseline Road in southwest Little Rock.

In northern Arkansas, flash flooding is predicted in Clinton, Mountain Home and Heber Springs. Forecasters warn that the valleys in the Ozark Mountains are dangerous during periods of heavy rain. Forecasters also warn of flash flooding in northwest Arkansas.

In southern Arkansas, a flash flooding warning was issued for the Huttig area in eastern Union County.

The National Weather Service in Kansas City issued a flood warning Wednesday morning for Moniteau Creek near Fayette, Missouri. The warning is in effect until Thursday afternoon.

The heavy rains took out a bridge southeast of Oklahoma City. But a group of residents left cut off by the washed out bridge are getting help from people they don't even know.

A handful of contractors showed up Tuesday with bulldozers, backhoes and dump trucks to help move the mud and divert a creek that flooded and loosened the dirt and gravel surrounding the span. They told the Associated Press that they're hoping to have the structure rebuilt in the next few days.

The bridge is on private property and owned by a homeowners association. By law it can't be maintained by Oklahoma City or Cleveland County. The association doesn't have enough money to pay for the repairs.

Association member Brenda Rickman says once the bridge is patched, the association will look for ways to finance a permanent fix.

The slow, strong storms are also slogging through Louisiana, making a major mess from the Arkansas border south to the Gulf of Mexico.

Heavy rains closed at least a dozen school systems Wednesday in the west and Cajun country. On the coast, days of strong southerly winds ahead of the storms prompted flood warnings and halted vessel traffic in some waterways. Heavy rain was expected to spread east into the Baton Rouge and New Orleans metro areas Wednesday.

Roger Erickson of the National Weather Service says up to a foot of rain fell by late Tuesday in a narrow strip of western Calcasieu and Beauregard parishes. High winds downed power lines and trees Tuesday from Union Parish in north-central Louisiana to Calcasieu Parish in the southwest.